Picture of The Weekhttp://www.eso.org/Picture of The Week FeedenMon, 19 Feb 2018 06:00:00 +0100Venus shines onhttp://www.eso.org/public/images/potw1808a/<img src="https://cdn.eso.org/images/news/potw1808a.jpg" border="0" align="left" /><p><span> </span></p>
<p dir="ltr"><span>This image, taken by ESO </span><a href="http://eso.org/public/outreach/partnerships/photo-ambassadors/"><span>Photo Ambassador </span></a><span> </span><span>Petr Horálek,</span><span> shows the planet </span><a href="https://en.wikipedia.org/wiki/Venus"><span>Venus</span></a><span> shining brightly over </span><a href="http://eso.org/public/teles-instr/paranal/"><span>ESO’s Paranal Observatory</span></a><span> in Chile at twilight. The featured telescope is the Very Large Telescope’s </span><a href="http://eso.org/public/teles-instr/vlt/auxiliarytelescopes/"><span>Auxiliary Telescope 1</span></a><span>, open and preparing itself to observe the night sky, which is splashed in shades of blue and orange. </span></p>
<p><span>ESO’s </span><a href="http://eso.org/public/teles-instr/paranal/"><span>Very Large Telescope (VLT) </span></a><span> </span><span>comprises four 8.2-metre Unit Telescopes, and four 1.8-metre Auxiliary Telescopes (ATs) — like the one posing in the foreground of the image — whose captured light can be combined to form the </span><a href="https://en.wikipedia.org/wiki/Very_Large_Telescope#Interferometry_and_the_VLTI"><span>VLT Interferometer (VLTI)</span></a><span>. By combining the light from multiple telescopes positioned in different places across the observatory site, the VLTI allows astronomers to see details up to 25 times finer than with the individual telescopes.</span></p>
<p>The light beams are then combined using a complex system of mirrors in underground tunnels where the light paths must be kept equal to distances less than 1/1000 mm over a hundred metres. This unbelievable technology means the VLTI can reconstruct images with an angular resolution of milliarcseconds — equivalent to distinguishing the two headlights of a car at the distance of the Moon.</p>Mon, 19 Feb 2018 06:00:00 +0100http://www.eso.org/public/images/potw1808a/A red giant sheds its skinhttp://www.eso.org/public/images/potw1807a/<img src="https://cdn.eso.org/images/news/potw1807a.jpg" border="0" align="left" /><p>This ghostly image features a distant and pulsating <a href="https://en.wikipedia.org/wiki/Red_giant">red giant star</a> known as R Sculptoris. Situated 1200 light-years away in the constellation of <a href="https://en.wikipedia.org/wiki/Sculptor_(constellation)">Sculptor</a>, R Sculptoris is something known as a <a href="https://en.wikipedia.org/wiki/Carbon_star">carbon-rich</a> <a href="https://en.wikipedia.org/wiki/Asymptotic_giant_branch"> asymptotic giant branch</a> (AGB) star, meaning that it is nearing the end of its life. At this stage, low- and intermediate-mass stars cool off, create extended atmospheres, and lose a lot of their mass — they are on their way to becoming spectacular <a href="https://en.wikipedia.org/wiki/Planetary_nebula">planetary nebulae</a>.</p>
<p>While the basics of this mass-loss process are understood, astronomers are still investigating how it begins near the surface of the star. The amount of mass lost by a star actually has huge implications for its stellar evolution, altering its future, and leading to different types of planetary nebulae. As AGB stars end their lives as planetary nebulae, they produce a vast range of elements — including 50% of elements heavier than iron — which are then released into the Universe and used to make new stars, planets, moons, and eventually the building blocks of life.</p>
<p>One particularly intriguing feature of R Sculptoris is its dominant bright spot, which looks to be two or three times brighter than the other regions. The astronomers that captured this wonderful image, using ESO’s <a href="http://www.eso.org/sci/facilities/paranal/telescopes/vlti.html">Very Large Telescope Interferometer</a> (VLTI), have concluded that R Sculptoris is surrounded by giant “clumps” of stellar dust that are peeling away from the shedding star. This bright spot is, in fact, a region around the star with little to no dust, allowing us to look deeper into the stellar surface.</p>
<p>This image captures an extremely small section of the sky: approximately 20x20 milli<a href="https://en.wikipedia.org/wiki/Minute_and_second_of_arc">arcseconds</a>. For comparison, Jupiter has an <a href="https://en.wikipedia.org/wiki/Angular_diameter">angular size</a> of approximately 40 arcseconds.</p>
<h3 dir="ltr">Links</h3>
<ul>
<li dir="ltr">
<p dir="ltr"><a href="https://arxiv.org/abs/1702.02574">Research paper</a></p>
</li>
</ul>Mon, 12 Feb 2018 06:00:00 +0100http://www.eso.org/public/images/potw1807a/Mapping a Mergerhttp://www.eso.org/public/images/comparisons/potw1806a/<img src="/public/archives/imagecomparisons/news/potw1806a.jpg" border="0" align="left" /><p>This unusual image reveals the aftermath of a catastrophic collision between two galaxies, which happened about one billion years ago. The result? A single, very oddly shaped galaxy named NGC 7252, and curiously nicknamed the <a href="https://www.spacetelescope.org/images/potw1549a/">Atoms for Peace</a> galaxy.</p>
<p>At the heart of this merger remnant lies a fascinating “minispiral” — a rotating disc of glowing gas, bursting with <a href="https://en.wikipedia.org/wiki/Star_formation">star formation</a>. Using the <a href="http://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/vimos/">VIsible Multi-Object Spectrograph</a> (VIMOS) instrument on ESO’s <a href="http://www.eso.org/public/teles-instr/paranal-observatory/vlt/">Very Large Telescope</a>, astronomers were able to measure the movement of the gas within this disc, allowing them to map its rotation. Red regions indicate gas moving away from us, and blue regions towards us. Together, these colours reveal the galaxy's steadily rotating centre, as well as highlighting two flowing streams of hot gas north-west and south-east of the central region. Past studies suggested that the central spiral was rotating counter to the rest of the galaxy, but by comparing the movement of stars around the galaxy with the gas <a href="https://en.wikipedia.org/wiki/Ionization">ionised</a> by newly formed stars in the minispiral, we now know that they are in fact rotating in the same direction.</p>
<p>Such a detailed map is possible due to the <a href="https://www.eso.org/public/teles-instr/technology/ifu/">Integral Field Unit</a> (IFU) on VIMOS, allowing astronomers to study the gas in NGC 7252 with a comprehensive "mosaic" view. Much like the way a fly observes the world, an IFU divides its subject into many cells, or pixels, generating a spectrum for every single one. The resulting information is arranged into a 3D data cube, which is particularly useful in studying extended objects in just one shot.</p>
<p>Using the slider, this new VLT map can be overlaid on an older image from the<a href="https://www.spacetelescope.org/"> NASA/ESA Hubble Space Telescope</a>, matching the galaxy’s visual beauty to its complex inner workings.</p>
<h3>Links</h3>
<ul>
<li><a href="https://arxiv.org/pdf/1801.09691.pdf">Science paper</a></li>
</ul>Mon, 05 Feb 2018 06:00:00 +0100http://www.eso.org/public/images/comparisons/potw1806a/A diamond in the roughhttp://www.eso.org/public/images/potw1805a/<img src="https://cdn.eso.org/images/news/potw1805a.jpg" border="0" align="left" /><p><span> </span></p>
<p dir="ltr"><span>Squint or you’ll miss it! At the very centre of this image, taken with the </span><a href="http://eso.org/public/teles-instr/vlt/vlt-instr/vimos/"><span>VIMOS</span></a><span> instrument attached to ESO’s Very Large Telescope (</span><a href="http://eso.org/public/teles-instr/paranal/"><span>VLT</span></a><span>), you can just about see the faint and fuzzy blue form of a distant galaxy known as the </span><a href="https://en.wikipedia.org/wiki/Sagittarius_Dwarf_Irregular_Galaxy"><span>Sagittarius Dwarf Irregular Galaxy</span></a><span>. </span></p>
<p dir="ltr"><span>Discovered in 1977 with the ESO </span><a href="http://eso.org/public/teles-instr/lasilla/1mschmidt/"><span>1-metre Schmidt telescope</span></a><span>, situated at ESO’s </span><a href="http://eso.org/public/teles-instr/lasilla/"><span>La Silla</span></a><span> observatory, the irregularly shaped — hence the name — dwarf galaxy is approximately 3 million light-years away in the constellation of </span><a href="https://en.wikipedia.org/wiki/Sagittarius_(constellation)"><span>Sagittarius</span></a><span> (The Archer). It is the most distant member of the Local Group of galaxies, of which the Milky Way is a member.</span></p>
<p dir="ltr"><span>Unlike normal galaxies, dwarf galaxies are typically smaller and host a relatively small number of stars. Gravitational tugs from nearby galaxies can often distort the spherical and disc-like shapes of these fragile galaxies — this very process may be responsible for the slightly rectangular shape of this particular dwarf galaxy.<br /><br />Acknowledgement: M. Bellazzini et al.</span></p>
<p dir="ltr"><span><br /></span></p>Mon, 29 Jan 2018 06:00:00 +0100http://www.eso.org/public/images/potw1805a/Desert vistashttp://www.eso.org/public/images/potw1804a/<img src="https://cdn.eso.org/images/news/potw1804a.jpg" border="0" align="left" /><p>The rugged terrain of the Chilean Atacama Desert offers a truly striking backdrop for photographs — as evidenced by this snap of ESO’s Visible and Infrared Survey Telescope for Astronomy (<a href="http://www.eso.org/public/teles-instr/surveytelescopes/vista/">VISTA</a>), taken by <a href="http://www.eso.org/public/outreach/partnerships/photo-ambassadors/">ESO Photo Ambassador</a> Alexandru Tudorică at ESO’s Paranal Observatory.</p>
<p>Although it is by far Tudorică’s most prominent subject, VISTA is not the only telescope visible in this image. The snaking path trailing off to the right side of the image leads to the inconspicuous enclosure of the <a href="http://www.ngtransits.org/">Next Generation Transit Survey</a> (NGTS) — the enclosure itself is just about visible to the far right of the frame, illuminated by a sliver of sunlight.</p>
<p>The NGTS comprises an array of small robotic telescopes that constantly and precisely monitor the brightness of nearby stars. By doing so, it hopes to catch exoplanets the size of Neptune in the act of <a href="https://en.wikipedia.org/wiki/Methods_of_detecting_exoplanets#Transit_photometry">blocking out light from their parent stars</a> as they transit across the face of their star and cross the line of sight to Earth.</p>Mon, 22 Jan 2018 06:00:00 +0100http://www.eso.org/public/images/potw1804a/Seeing stars in a mountain environmenthttp://www.eso.org/public/images/potw1803a/<img src="https://cdn.eso.org/images/news/potw1803a.jpg" border="0" align="left" /><p>These 56 smiling students took part in <a href="https://www.eso.org/public/announcements/ann17081/">ESO’s Winter Astronomy Camp 2017</a>, which explored the theme of “Distances in the Universe”. The young astronomy enthusiasts enjoyed several astronomical sessions, including lectures, hands-on activities and night-time observations using professional telescopes. They also tried their hand at various winter sports and excursions.</p>
<p>The Camp was held at the <a href="http://www.oavda.it/english/">Astronomical Observatory of the Autonomous Region of the Aosta Valley</a>, surrounded by the natural beauty of the Italian Alps, close to some of Europe’s highest mountains and under some of the clearest skies. The observatory is equipped with seven telescopes that were devoted to camp activities.</p>
<p>The camp, organised by <a href="http://www.sterrenlab.com">Sterrenlab</a>, took place between 26 December 2017 and 1 January 2018, and was open to students aged 16–18. Later this year, the <a href="https://www.eso.org/public/announcements/ann17034/">ESO Summer Astronomy Camp</a> will be held under the dark skies of northern Portugal, organised by the <a href="https://www.astro.up.pt/caup/index.php?Lang=uk">Centre for Astrophysics of the University of Porto</a> (CAUP).</p>Mon, 15 Jan 2018 06:00:00 +0100http://www.eso.org/public/images/potw1803a/Supermoon beckons in the new yearhttp://www.eso.org/public/images/potw1802a/<img src="https://cdn.eso.org/images/news/potw1802a.jpg" border="0" align="left" /><p>The first evening of the new year was beckoned in by a spectacular <a href="https://en.wikipedia.org/wiki/Supermoon">supermoon</a>, rising up from behind the majestic <a href="https://en.wikipedia.org/wiki/Cerro_Armazones">Cerro Armazones</a> mountain in Chile. A supermoon like this is a magnificent, albeit relatively frequent, occurrence which takes place when a full moon coincides with the point in the lunar orbit that is closest to Earth, its diameter appearing about 14% larger in the sky.</p>
<p>The road zigzagging up Cerro Armazones appears to lead directly to the Moon itself — truly making it a road to the stars. By 2024, the “world’s biggest eye on the sky” will rest on top of this mountain, as its peak will be home to the <a href="https://www.eso.org/public/teles-instr/elt/">Extremely Large Telescope</a>. At an altitude of 3046 metres, Cerro Armazones provides a spectacular environment for astronomical observations, in particular because it receives 320 clear nights per year.</p>
<p>This photo was captured by ESO<a href="http://www.eso.org/public/outreach/partnerships/photo-ambassadors.html"> Photo Ambassador</a> Gerhard Hüdepohl. He walked two kilometres from ESO’s nearby <a href="https://www.eso.org/public/teles-instr/paranal-observatory/">Paranal Observatory</a> into the Atacama Desert to find the right position to take this photo. Beforehand, he had calculated the path the Moon would take to know the right time and place for this extraordinary shot.</p>Mon, 08 Jan 2018 06:00:00 +0100http://www.eso.org/public/images/potw1802a/Ribbons and pearlshttp://www.eso.org/public/images/potw1801a/<img src="https://cdn.eso.org/images/news/potw1801a.jpg" border="0" align="left" /><p>This week’s picture shows spectacular ribbons of gas and dust wrapping around the pearly centre of the barred spiral galaxy <a href="https://en.wikipedia.org/wiki/NGC_1398">NGC 1398</a>. This galaxy is located in the constellation of Fornax (The Furnace), approximately 65 million light-years away.</p>
<p>Rather than beginning at the very middle of the galaxy and swirling outwards, NGC 1398’s graceful spiral arms stem from a <a href="https://en.wikipedia.org/wiki/Barred_spiral_galaxy">straight bar</a>, formed of stars, that cuts through the galaxy’s central region. Most spiral galaxies — around two thirds — are observed to have this feature, but it’s not yet clear whether or how these bars affect a galaxy’s behaviour and development.</p>
<p>This image comprises data gathered by the FOcal Reducer/low dispersion Spectrograph 2 (<a href="http://eso.org/public/teles-instr/vlt/vlt-instr/fors/">FORS2</a>) instrument, mounted on ESO’s Very Large Telescope (<a href="http://eso.org/public/teles-instr/paranal/">VLT</a>) at Paranal Observatory, Chile. It shows NGC 1398 in striking detail, from the dark lanes of dust mottling its spiral arms, through to the pink-hued star-forming regions sprinkled throughout its outer regions.</p>
<p><span><span>This image was created as part of the</span><a href="http://www.eso.org/public/outreach/gems.html"><span> ESO Cosmic Gems programme</span></a><span>, an outreach initiative to produce images of interesting, intriguing or visually attractive objects using ESO telescopes, for the purposes of education and public outreach. The programme makes use of telescope time that cannot be used for science observations. All data collected may also be suitable for scientific purposes, and are made available to astronomers through ESO’s science archive.</span></span></p>Mon, 01 Jan 2018 06:00:00 +0100http://www.eso.org/public/images/potw1801a/Comparison image: HAWK-I and Hubble Explore a Cluster with the Mass of two Quadrillion Sunshttp://www.eso.org/public/images/comparisons/potw1752a/<img src="/public/archives/imagecomparisons/news/potw1752a.jpg" border="0" align="left" /><p>This image shows something spectacular: a galaxy cluster so massive that it is warping the space around it! The cluster, whose heart is at the centre of the frame, is named RCS2 J2327, and is one of the most massive clusters known at its distance or beyond.</p>
<p>Massive objects such as RCS2 J2327 have such a strong influence on their surroundings that they actually warp the space around them — this effect is known as <a href="https://en.wikipedia.org/wiki/Gravitational_lens">gravitational lensing</a>, and can cause light from more distant objects to be bent, distorted, and amplified, allowing us to see galaxies that would otherwise be far too distant for us to detect. Gravitational lensing is one of the predictions of Albert Einstein's <a href="https://en.wikipedia.org/wiki/General_relativity">General Theory of Relativity</a> and can be observed in three different regimes: strong lensing, weak lensing, and microlensing. Unlike <a href="https://en.wikipedia.org/wiki/Strong_gravitational_lensing">strong lensing</a>, which produces stunning images of distorted galaxies, sweeping arcs, and phenomena known as <a href="https://en.wikipedia.org/wiki/Einstein_ring">Einstein rings</a>, <a href="https://en.wikipedia.org/wiki/Weak_gravitational_lensing">weak gravitational lensing</a> is mostly studied statistically — but offers a way to measure the masses of cosmic objects, as shown here.</p>
<p>This image is a composite of observations from the <a href="http://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/hawk-i/">HAWK-I</a> instrument on ESO’s <a href="http://www.eso.org/public/teles-instr/paranal-observatory/vlt/">Very Large Telescope</a> and the <a href="https://www.spacetelescope.org/">NASA/ESA Hubble Space Telescope</a>’s <a href="http://spacetelescope.org/about/general/instruments/acs/">Advanced Camera for Surveys</a>, and demonstrates an impressively detailed collaborative approach to studying weak lensing in the cosmos. The study found RCS2 J2327 to contain the mass of two quadrillion Suns!</p>
<p>Using the slider a mass map becomes visible, showing the amount of mass thought to be contained within each part of the cluster. The creation of the map was only possible due to the exact measurements on the amount of gravitational lensing in the different areas of the cluster.</p>
<h3>Links:</h3>
<ul>
<li><a href="http://www.eso.org/public/images/potw1752a/">HAWK-I and Hubble Explore a Cluster with the Mass of two Quadrillion Suns</a></li>
<li><a href="http://www.eso.org/public/images/potw1752b/">Galaxy Cluster RCS2 J2327</a></li>
<li><a href="https://arxiv.org/pdf/1711.00475.pdf">Paper by Schrabback et al.</a></li>
</ul>Mon, 25 Dec 2017 06:00:00 +0100http://www.eso.org/public/images/comparisons/potw1752a/Season’s Greetings from the European Southern Observatory!http://www.eso.org/public/images/potw1751a/<img src="https://cdn.eso.org/images/news/potw1751a.jpg" border="0" align="left" /><p><a href="https://www.eso.org/public/xmas17/">Season's Greetings</a> on behalf of everyone at the European Southern Observatory! We wish you a jolly end of the year and a fruitful 2018!</p>
<h3>Links</h3>
<ul>
<li><a href="https://www.eso.org/public/xmas17/">Christmas card 2017</a></li>
</ul>Mon, 18 Dec 2017 06:00:00 +0100http://www.eso.org/public/images/potw1751a/Supermoon at La Sillahttp://www.eso.org/public/images/potw1750a/<img src="https://cdn.eso.org/images/news/potw1750a.jpg" border="0" align="left" /><p dir="ltr">This image captures the moment that a <a href="https://en.wikipedia.org/wiki/Supermoon">supermoon</a> seemed to rest on top of the Chilean mountains, seen from 4.5 kilometres distance from the summit of <a href="https://www.eso.org/public/teles-instr/lasilla/">La Silla</a>. Although not terribly interesting from a scientific perspective, during this relatively rare event the Moon is a little closer to Earth, making its diameter appear about 10% larger in the sky.</p>
<p dir="ltr">A supermoon occurs when a full Moon coincides with its <a href="https://en.wikipedia.org/wiki/Apsis">perigee</a> — the point in the Moon’s elliptical <a href="https://en.wikipedia.org/wiki/Orbit_of_the_Moon">orbit</a> at which it is nearest to Earth. A <a href="https://en.wikipedia.org/wiki/Full_moon">full Moon</a> occurs on average every 30 days, and is at its perigee every 28 days. Three or four times a year these two events occur at almost the same time, creating a supermoon. An astrologer, Richard Nolle, first coined the term supermoon over 30 years ago, but it has only recently come into popular astronomical usage. Before they were known as supermoons, astronomers referred to them as perigee full Moons, but neither title has brought with it a precise definition of when exactly the supermoon occurs.</p>
<p dir="ltr">No matter what we call them, supermoons — like all full Moons — have real physical effects on Earth. Full moons act with the Sun to create larger than usual tides, known as <a href="https://en.wikipedia.org/wiki/Tide#Range_variation:_springs_and_neaps">spring tides</a>. But when the full Moon is also at its perigee, its gravitational pull is even larger and Earth’s tides become ever bigger, known as <a href="https://en.wikipedia.org/wiki/Perigean_spring_tide">perigean spring tides</a>.</p>Mon, 11 Dec 2017 06:00:00 +0100http://www.eso.org/public/images/potw1750a/VLT’s SPHERE spies rocky worldshttp://www.eso.org/public/images/potw1749a/<img src="https://cdn.eso.org/images/news/potw1749a.jpg" border="0" align="left" /><p><span> </span></p>
<p dir="ltr"><span>These images were taken by ESO’s </span><a href="https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/sphere/"><span>SPHERE</span></a><span> (Spectro-Polarimetric High-contrast Exoplanet REsearch) instrument, installed on ESO’s </span><a href="http://www.eso.org/public/teles-instr/paranal-observatory/vlt/"><span>Very Large Telescope</span></a><span> (VLT) at the Paranal Observatory, Chile. </span><span>These strikingly-detailed views reveal four of the millions of rocky bodies in the main </span><a href="https://en.wikipedia.org/wiki/Asteroid_belt"><span>asteroid belt</span></a><span>, a ring of asteroids between Mars and Jupiter that separates the rocky inner planets of the Solar System from the gaseous and icy outer planets.</span></p>
<p dir="ltr"><span> </span></p>
<p dir="ltr"><span>Clockwise from top left, the asteroids shown here are </span><a href="https://en.wikipedia.org/wiki/29_Amphitrite"><span>29 Amphitrite</span></a><span>, </span><a href="https://en.wikipedia.org/wiki/324_Bamberga"><span>324 Bamberga</span></a><span>, </span><a href="https://en.wikipedia.org/wiki/2_Pallas"><span>2 Pallas</span></a><span>, and </span><a href="https://en.wikipedia.org/wiki/89_Julia"><span>89 Julia</span></a><span>. Named after the greek goddess </span><a href="https://en.wikipedia.org/wiki/Athena"><span>Pallas Athena</span></a><span>, 2 Pallas is about 510 kilometres wide. This makes it the third largest asteroid in the main belt and one of the biggest asteroids in the entire Solar System. It contains about 7% of the mass of the entire asteroid belt — so hefty that it was once classified as a planet. A third of the size of 2 Pallas, 89 Julia is thought to be named after </span><a href="https://en.wikipedia.org/wiki/Julia_of_Corsica"><span>St Julia of Corsica</span></a><span>. Its stony composition led to its classification as an </span><a href="https://en.wikipedia.org/wiki/S-type_asteroid"><span>S-type</span></a><span> asteroid. Another S-type asteroid is 29 Amphitrite, which was only discovered in 1854. 324 Bamberga, one of the largest </span><a href="https://en.wikipedia.org/wiki/C-type_asteroid"><span>C-type</span></a><span> asteroid in the asteroid belt, was discovered even later: </span><a href="https://en.wikipedia.org/wiki/Johann_Palisa"><span>Johann Palisa</span></a><span> found it in 1892. Today, it is understood that C-type asteroids may actually be bodies from the outer Solar System following the migration of the giant planets. As such, they may contain ice in their interior.</span></p>
<p dir="ltr"><span> </span></p>
<p><span>Although the asteroid belt is often portrayed in science fiction as a place of violent collisions, packed full of large rocks too dangerous for even the most skilled of space pilots to navigate, it is actually very sparse. In total, the asteroid belt contains just 4% of the mass of the Moon, with about half of this mass contained in the four largest residents: </span><a href="https://en.wikipedia.org/wiki/Ceres_(dwarf_planet)"><span>Ceres</span></a><span>, </span><a href="https://en.wikipedia.org/wiki/4_Vesta"><span>4 Vesta</span></a><span>, 2 Pallas, and </span><a href="https://en.wikipedia.org/wiki/10_Hygiea"><span>10 Hygiea</span></a><span>.</span></p>Mon, 04 Dec 2017 06:00:00 +0100http://www.eso.org/public/images/potw1749a/The Planetarium and the Sun Pillarhttp://www.eso.org/public/images/potw1748a/<img src="https://cdn.eso.org/images/news/potw1748a.jpg" border="0" align="left" /><p>A clear sky, a striking sunset, and the futuristic curves of a state-of-the-art planetarium and visitor centre — what more could you ask for in an ESO <a href="https://www.eso.org/public/images/potw/">Picture of the Week</a>?</p>
<p>However, this image has something else up its sleeve to delight us: a <a href="https://en.wikipedia.org/wiki/Light_pillar">sun pillar</a>. This softly-glowing column of light seems to rise from the horizon near the setting Sun, illuminating the sky above it. This illusion is created by millions of tiny ice crystals — usually flat and hexagonal in shape — in our atmosphere, which reflect sunlight to form an apparent beam. Sun pillars are typically seen when the Sun is low in the sky, or when it has dipped below the horizon.</p>
<p>The last rays of sunlight have also interacted with particles in the clouds above, which have scattered the light to create a brilliant array of oranges, yellows, reds, and pinks in the sky above the <a href="https://supernova.eso.org">ESO Supernova Planetarium &amp; Visitor Centre</a>. The ESO Supernova is the newest building on site of the <a href="https://www.eso.org/public/about-eso/travel/garching/">ESO’s Headquarters</a> in Garching bei München, Germany. After its opening in April 2018, this cutting-edge centre will engage visitors with frontline science and ESO’s world-leading observing facilities.</p>Mon, 27 Nov 2017 06:00:00 +0100http://www.eso.org/public/images/potw1748a/MUSE spies accreting giant structure around a quasarhttp://www.eso.org/public/images/potw1747a/<img src="https://cdn.eso.org/images/news/potw1747a.jpg" border="0" align="left" /><p><span> </span></p>
<p dir="ltr"><span>This Picture of the Week shows a huge cloud of gas around the distant </span><a href="https://en.wikipedia.org/wiki/Quasar"><span>quasar</span></a><span> SDSS J102009.99+104002.7, taken by the </span><a href="https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/muse/"><span>Multi Unit Spectroscopic Explorer</span></a><span> (MUSE) instrument on ESO’s </span><a href="https://www.eso.org/public/teles-instr/paranal-observatory/vlt/"><span>Very Large Telescope</span></a><span> (VLT) at the </span><a href="https://www.eso.org/public/teles-instr/paranal-observatory/"><span>Paranal Observatory</span></a><span>. Quasars are the luminous centres of </span><a href="https://en.wikipedia.org/wiki/Active_galactic_nucleus"><span>active galaxies</span></a><span>, which are kept active by material falling onto the central </span><a href="https://en.wikipedia.org/wiki/Supermassive_black_hole"><span>supermassive black hole</span></a><span>. This quasar and its surrounding cloud are at a redshift larger than 3, meaning that they are seen as they were only about 2 billion years after the Big Bang.</span></p>
<p dir="ltr"><span>The cloud of gas (or nebula) surrounding the quasar is known to astronomers as an Enormous Lyman-Alpha Nebula (ELAN). These types of nebula are massive structures of gas which formed in the early Universe, and they can help astronomers to learn how angular momentum — which explains the observed rotation of more recent galaxies — was created in the Universe. Thanks to the revolutionary MUSE instrument, it is now possible to observe these rare giant nebulae in greater detail than ever before. </span></p>
<p dir="ltr"><span>This particular ELAN has a diameter of about a million light-years, and MUSE’s spectral imaging capabilities have allowed astronomers to measure the signature of inspiraling motions within the nebula — for the first time ever.</span></p>
<p dir="ltr"><strong>Link</strong></p>
<ul>
<li><span><a href="https://arxiv.org/pdf/1709.08228.pdf">Science paper on arXiv</a><br /></span></li>
</ul>Mon, 20 Nov 2017 06:00:00 +0100http://www.eso.org/public/images/potw1747a/A gigantic cosmic bubblehttp://www.eso.org/public/images/potw1746a/<img src="https://cdn.eso.org/images/news/potw1746a.jpg" border="0" align="left" /><p>Measuring more than 300 000 light-years across, three times the diameter of the Milky Way, this colourful bubble of <a href="https://en.wikipedia.org/wiki/Ionization">ionised</a> gas is the biggest to ever have been discovered. The enormous bubble contains 10 individual galaxies and is situated in a particularly dense region of a galaxy group called COSMOS-Gr30, 6.5 billion light-years away from Earth. Targeted due to its high density of galaxies, this group is extremely varied — some galaxies are actively forming stars while others are passive; some are bright while others are dim; some are massive and others are tiny.</p>
<p>This record-breaking bubble was discovered and studied in detail thanks to the incredible sensitivity of the <a href="http://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/muse/">MUSE</a> instrument, mounted on ESO’s <a href="http://www.eso.org/public/teles-instr/paranal-observatory/vlt/">Very Large Telescope</a>. Operating in visible wavelengths, MUSE combines the capabilities of an imaging device with the measuring capacity of a spectrograph, creating a unique and powerful tool that can shed light on cosmological objects that would otherwise remain in the dark.</p>
<p>MUSE’s powerful eye on the sky has allowed astronomers to understand that this large pocket of gas is not pristine, but was expelled from galaxies either during violent interactions or by superwinds driven by active black holes and supernovae. They also studied how this magnificent bubble became ionised. It is believed that the gas in the upper area (shown in blue) was ionised by intense electromagnetic radiation from newborn stars and shock waves stemming from galactic activity. Astronomers suspect that the violent red <a href="https://www.eso.org/public/videos/activegalaxy_HEU/">active galactic nucleus</a> towards the lower left of the image could have ripped the electrons from their atoms.</p>
<h3>Links</h3>
<ul>
<li><a href="https://www.eso.org/public/images/comparisons/potw1746a/">Slider comparison of the galaxy group COSMOS-Gr30 seen with Hubble and MUSE</a></li>
<li><a href="https://www.eso.org/public/images/potw1746b/">COSMOS-Gr30 seen with the NASA/ESA Hubble Space Telescope</a></li>
<li><a href="https://www.eso.org/public/archives/releases/sciencepapers/potw1746/potw1746a.pdf">Research paper</a></li>
</ul>Mon, 13 Nov 2017 06:00:00 +0100http://www.eso.org/public/images/potw1746a/Cocooned on Cerro Paranalhttp://www.eso.org/public/images/potw1745a/<img src="https://cdn.eso.org/images/news/potw1745a.jpg" border="0" align="left" /><p>As the Sun sets, the last rays of the day creep through to illuminate ESO’s <a href="http://www.eso.org/public/teles-instr/vlt/">Very Large Telescope (VLT)</a> as it prepares for another night of cosmos-gazing! This unusual angle reveals the industrial interior of one of the four 8.2-metre Unit Telescopes that comprise the VLT, situated atop Cerro Paranal, Chile.</p>
<p>The Unit Telescope enclosures play a vital role in preserving the VLT’s position as the foremost astronomical ground-based observatory in the world. The vast air-conditioning system — seen in this image as the metallic tubing snaking around the telescope — and state-of-the-art dome work together to maintain the perfect observing environment. This housing shelters the telescope from its harsh surroundings and at night shields the sensitive instruments from windy weather conditions, which could warp the shape of the thin primary mirror and blur the observations.</p>
<p>The photo was taken by <a href="http://www.eso.org/public/germany/outreach/partnerships/photo-ambassadors/#tudorica">ESO Photo Ambassador</a> Alexandru Tudorică.</p>Mon, 06 Nov 2017 06:00:00 +0100http://www.eso.org/public/images/potw1745a/Antares overlooking an Auxiliary Telescopehttp://www.eso.org/public/images/potw1744a/<img src="https://cdn.eso.org/images/news/potw1744a.jpg" border="0" align="left" /><p><span>
<p dir="ltr"><span>Brilliant blue stars litter the southern sky and the </span><a href="http://en.wikipedia.org/wiki/Spiral_galaxy#Galactic_bulge"><span>galactic bulge</span></a><span> of our home galaxy, the Milky Way, hangs serenely above the horizon in this spectacular shot of ESO’s Paranal Observatory.</span></p>
<p dir="ltr"><span>This image was taken atop Cerro Paranal in Chile, home to ESO’s </span><a href="http://eso.org/paranal"><span>Very Large Telescope</span></a><span> (VLT). In the foreground, the open dome of one of the four 1.8-metre </span><a href="http://www.eso.org/public/teles-instr/vlt/auxiliarytelescopes/"><span>Auxiliary Telescopes</span></a><span> can be seen. The four Auxiliary Telescopes can be utilised together, to form the </span><a href="http://www.eso.org/public/teles-instr/technology/interferometry/"><span>Very Large Telescope Interferometer</span></a><span> (VLTI).</span></p>
<span>The plane of the Milky Way is dotted with bright regions of hot gas. The very bright star towards the upper left corner of the frame is </span><a href="http://en.wikipedia.org/wiki/Antares"><span>Antares</span></a><span> — the brightest star in </span><a href="http://en.wikipedia.org/wiki/Scorpius"><span>Scorpius</span></a><span> and the fifteenth brightest star in the night sky.</span></span></p>Mon, 30 Oct 2017 06:00:00 +0100http://www.eso.org/public/images/potw1744a/ESO Open House Day 2017http://www.eso.org/public/images/potw1743a/<img src="https://cdn.eso.org/images/news/potw1743a.jpg" border="0" align="left" /><p>On Saturday 21 October, ESO Headquarters in Garching, Germany, opened its doors for the yearly Open House Day. In conjunction with other facilities based on the science campus in Garching, ESO invited visitors to experience first-hand its work as the world’s leading ground-based astronomy organisation.</p>
<p>Before the doors had even opened at 11:00, people were waiting outside, eager to experience all the different activities available. In total, a record-breaking 5600 people seized the opportunity to have their questions answered by experienced astronomers and to see what’s going on at an organisation at the forefront of astronomical research. The programme included live experiments (like the comet-making experiment here), guided tours, an exhibition on the ESO observatories, talks from ESO scientists, and a live connection to the ESO observatories in Chile. Visitors could also test some of the interactive demonstrations which will be on display in the exhibition of the <a href="https://supernova.eso.org/">ESO Supernova Planetarium &amp; Visitor Centre.</a></p>
<p>ESO is already looking forward to the Open House Day 2018, which will also include the new ESO Supernova.</p>
<p>To view more photos from the event, visit our Facebook album. If you participated in the Open House Day 2017 and took pictures, we invite you to share them on the <a href="https://www.flickr.com/groups/youresopictures/">Your ESO Pictures</a> Flickr group.</p>Mon, 23 Oct 2017 06:00:00 +0200http://www.eso.org/public/images/potw1743a/Caught in a Dust Traphttp://www.eso.org/public/images/potw1742a/<img src="https://cdn.eso.org/images/news/potw1742a.jpg" border="0" align="left" /><p>This image from the <a href="http://www.eso.org/public/teles-instr/alma/">Atacama Large Millimeter/submillimeter Array (ALMA)</a> shows V1247 Orionis, a young, hot star surrounded by a dynamic ring of gas and dust, known as a <a href="https://en.wikipedia.org/wiki/Circumstellar_disc">circumstellar disc</a>. This disc can be seen here in two parts: a clearly defined central ring of matter and a more delicate crescent structure located further out.</p>
<p>The region between the ring and crescent, visible as a dark strip, is thought to be caused by a young planet carving its way through the disc. As the planet orbits around its parent star, its motion creates areas of high pressure on either side of its path, similar to how a ship creates <a href="https://en.wikipedia.org/wiki/Bow_wave">bow waves</a> as it cuts through water. These areas of high pressure could become protective barriers around sites of planet formation; dust particles are trapped within them for millions of years, allowing them the time and space to clump together and grow.</p>
<p>The exquisite resolution of ALMA allows astronomers to study the intricate structure of such a dust trapping vortex for the first time. The image reveals not only the crescent-shaped dust trap at the outer edge of the dark strip, but also regions of excess dust within the ring, possibly indicating a second dust trap that formed inside of the potential planet’s orbit. This confirms the predictions of earlier computer simulations.</p>
<p>Dust trapping is one potential solution to a major stumbling block in current theories of how planets form, which predicts that particles should drift into the central star and be destroyed before they have time to grow to <a href="https://en.wikipedia.org/wiki/Planetesimal">planetesimal</a> sizes (the radial drift problem).</p>
<h3>Links</h3>
<ul>
<li><a href="https://www.eso.org/public/archives/releases/sciencepapers/potw1742/potw1742a.pdf">Science paper</a></li>
</ul>Mon, 16 Oct 2017 06:00:00 +0200http://www.eso.org/public/images/potw1742a/A high-tech family portraithttp://www.eso.org/public/images/potw1741a/<img src="https://cdn.eso.org/images/news/potw1741a.jpg" border="0" align="left" /><p>This family portrait was captured by veteran <a href="https://www.eso.org/public/outreach/partnerships/photo-ambassadors/">ESO Photo Ambassador</a> Alexandru Tudorică, and shows all of the telescopes residing at ESO’s <a href="http://www.eso.org/public/teles-instr/lasilla/">La Silla Observatory</a> in Chile.</p>
<p>Looming over its relatives, ESO’s <a href="http://www.eso.org/public/teles-instr/lasilla/36/">3.6-metre telescope</a> gleams on the far left of the image. Home to the High Accuracy Radial velocity Planet Searcher (<a href="http://www.eso.org/public/teles-instr/lasilla/36/harps/">HARPS</a>) instrument, the 3.6-metre telescope is the world’s foremost ground-based planet hunter. ESO’s New Technology Telescope (<a href="http://www.eso.org/public/teles-instr/lasilla/ntt/">NTT</a>) can be seen on an adjoining peak, easily visible as the next-largest family member. The NTT has been a testbed for pioneering technologies — such as <a href="http://www.eso.org/public/teles-instr/technology/active_optics/">active optics</a> — that are now standard features on telescopes around the world, including ESO’s Very Large Telescope (<a href="http://www.eso.org/public/teles-instr/paranal/">VLT</a>).</p>
<p>The smaller domes of more ESO-operated, collaborative, and decommissioned telescopes can be seen emerging from the mountain terrain, as can the site’s main access road, which winds up the sun-bathed mountainside towards the site’s various technical and support buildings.</p>Mon, 09 Oct 2017 06:00:00 +0200http://www.eso.org/public/images/potw1741a/VLTI Revisits the Largest Yellow Hypergiant Ever Discoveredhttp://www.eso.org/public/images/potw1740a/<img src="https://cdn.eso.org/images/news/potw1740a.jpg" border="0" align="left" /><p>It may not look like much, but this blob shows a remarkable star named V766 Centauri (V766 Cen for short) and its close companion. It was first <a href="https://www.eso.org/public/news/eso1409/">studied and classified a few years ago</a> by researchers using ESO's <a href="http://www.eso.org/sci/facilities/paranal/telescopes/vlti.html">Very Large Telescope Interferometer</a> (VLTI) when it was found to be something known as a <a href="https://en.wikipedia.org/wiki/Yellow_hypergiant">yellow hypergiant</a>, a massive and luminous type of star that is extremely rare — and extremely big! Measuring over 1400 times the diameter of the Sun, V766 Cen was not only the largest star of its type ever discovered, but also one of the ten largest stars ever found.</p>
<p>However, a recent study has instead suggested that V766 Cen is likely to be in the phase of life just prior to that of a yellow hypergiant: an evolved red supergiant, which is losing mass so fast that it will eventually transition back into a warmer yellow supergiant for a short period of time. Either way, the star is a true behemoth, and of huge interest to scientists wishing to understand more about this unusual stage in the life cycle of stars.</p>
<p>A team of scientists has now used the VLTI again to study V766 Cen in greater detail. Using the array’s four <a href="http://www.eso.org/public/teles-instr/paranal-observatory/vlt/auxiliarytelescopes/">auxiliary telescopes</a> and an instrument mounted on the VLTI known as <a href="http://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/pionier/">PIONIER</a> (the Precision Integrated-Optics Near-infrared Imaging ExpeRiment), the team imaged V766 Centauri and its close companion in striking detail. They found this companion to be smaller and cooler than its partner — likely a cool giant or supergiant with a radius of around 650 times that of the Sun. Close companions are thought to be typical for massive stars and are important in the processes of stellar evolution.</p>
<p>This Picture of the Week shows V766 Cen as it was seen over three periods of time. These images actually contain both V766 Cen and its companion — in the first image the companion is passing behind V766 Cen, but in the second and third images the companion is passing in front and is visible as a bright patch.</p>
<h3>Links</h3>
<ul>
<li><a href="https://www.eso.org/public/archives/releases/sciencepapers/potw1740/potw1740a.pdf">Research paper</a></li>
</ul>Mon, 02 Oct 2017 06:00:00 +0200http://www.eso.org/public/images/potw1740a/Stars and spiralshttp://www.eso.org/public/images/potw1739a/<img src="https://cdn.eso.org/images/news/potw1739a.jpg" border="0" align="left" /><p><span> </span></p>
<p dir="ltr"><span>This spectacular </span><span>spiral galaxy, known as NGC 1964, resides approximately 70 million light-years away in the constellation of </span><a href="https://en.wikipedia.org/wiki/Lepus_(constellation)"><span>Lepus (The Hare)</span></a><span>. NGC 1964 has a bright and dense core. This core sits within a mottled oval disc, which is itself encircled by distinct spiral arms speckled with bright starry regions. The brilliant centre of the galaxy caught the eye of the astronomer </span><a href="https://en.wikipedia.org/wiki/William_Herschel"><span>William Herschel</span></a><span> on the night of 20 November 1784, leading to the galaxy’s discovery and subsequent documentation in the </span><a href="https://en.wikipedia.org/wiki/New_General_Catalogue"><span>New General Catalogue</span></a><span>. </span></p>
<p dir="ltr"><span>In addition to containing stars, NGC 1964 lives in a star-sprinkled section of the sky. In this view from </span><span>the </span><a href="http://www.eso.org/public/teles-instr/lasilla/mpg22/wfi/"><span>Wide Field Imager</span></a><span> (WFI) — an instrument mounted on the </span><a href="http://www.eso.org/public/teles-instr/lasilla/mpg22/"><span>MPG/ESO 2.2-metre telescope</span></a><span> at ESO’s La Silla Observatory, Chile — the </span><span>star HD 36785 can be seen to the galaxy’s immediate right. Above it reside two other prominent stars named HD 36784 and TYC 5928-368-1 — and the large bright star below NGC 1964 is known as BD-22 1147. </span></p>
<p><span>This view of NGC 1964 also contains an array of galaxies, visible in the background. </span><span>The WFI is able to observe the light from these distant galaxies, and those up to 40 million times fainter than the human eye can see.</span></p>
<p> </p>Mon, 25 Sep 2017 06:00:00 +0200http://www.eso.org/public/images/potw1739a/The NTT and beyondhttp://www.eso.org/public/images/potw1738a/<img src="https://cdn.eso.org/images/news/potw1738a.jpg" border="0" align="left" /><p>Rising up to block part of the star-studded sky, the <a href="http://www.eso.org/public/teles-instr/lasilla/ntt/">New Technology Telescope</a> (NTT) cuts a striking and dramatic figure in this ESO Picture of the Week.</p>
<p>Located at ESO's <a href="http://eso.org/lasilla">La Silla Observatory</a> in the Chilean <a href="http://en.wikipedia.org/wiki/Atacama_Desert">Atacama Desert</a>, the NTT was inaugurated in 1989. It was the first ever telescope to have a computer-controlled main mirror. This 3.58-metre mirror is very flexible and its shape can be continuously changed, allowing astronomers to counteract <a href="https://en.wikipedia.org/wiki/Active_optics">deformations </a>due to external influences such as temperature and mechanical stress mid-observation in order to see the objects as clearly as possible.</p>
<p>Complementing the NTT’s groundbreaking technology is the innovative design of its housing. Its octagonal dome is relatively small and includes a series of flaps that ventilate the structure with reduced turbulence, allowing air to flow smoothly across the mirror. The dome walls can be opened entirely — as opposed to only opening the roof, as with conventional domes — to reveal large swathes of the southern sky.</p>
<p>This image was taken by <a href="http://www.eso.org/public/outreach/partnerships/photo-ambassadors/">ESO Photo Ambassador</a> Babak Tafreshi.</p>Mon, 18 Sep 2017 06:00:00 +0200http://www.eso.org/public/images/potw1738a/Do-it-yourself Science — is Proxima c hiding in this graph?http://www.eso.org/public/images/potw1737a/<img src="https://cdn.eso.org/images/news/potw1737a.jpg" border="0" align="left" /><p>This unusual Picture of the Week showcases the latest data gathered by ESO’s exoplanet hunter, the <a href="http://www.eso.org/public/teles-instr/lasilla/36/harps/">High Accuracy Radial velocity Planet Searcher</a> (HARPS), during the ongoing <a href="https://reddots.space/">Red Dots campaign</a>, a search for terrestrial planets around our nearest three red dwarf stars: Proxima Centauri, Barnard’s Star, and Ross 154. The <a href="http://www.eso.org/public/announcements/ann17036/?lang">campaign was launched earlier in 2017</a> to build on the 2016 <a href="http://www.eso.org/public/news/eso1629/">discovery</a> of Proxima b around our nearest stellar neighbour, Proxima Centauri. Red Dots is designed as an open notebook science experiment, meaning the public has access to the data and can even contribute observations. Can you see a new exoplanet in these data of Proxima Centauri?</p>
<p>By carefully tracing the movement of a star over time, graphs like these can reveal the presence of exoplanets. Just as a star pulls on its orbiting planets using gravity, planets pull on the star, causing the star to wobble and shift the wavelength of its light by a small but measureable amount. By analysing the predictable, repeating changes, astronomers can infer the presence of a planet. The top left graph displays the 2016 data that confirmed the existence of Proxima b, showing how the planet is causing its parent star, Proxima Centauri, to move towards and away from Earth over time. The curved line represents the wobbling signal of the star, with the regular pattern of changing radial velocities (RV) repeating every 11.2 days.</p>
<p>The top right graph shows new measurements made with HARPS during the Red Dots campaign. The new data once again confirms Proxima b’s signal (in yellow), but also includes additional data patterns — visible here as a downward slope in both the 2016 and 2017 data points — hinting that there may be more to be discovered. To make a firmer statement on what is causing these patterns, astronomers need to use quantitative mathematical tools.</p>
<p>One such mathematical tool is called a <a href="https://en.wikipedia.org/wiki/Periodogram">periodogram</a>, which searches for repeating signals in the data — displayed here as prominent peaks — that indicate the presence of a planet. The graph on the bottom panel shows the periodogram for the new data. The first signal (in white) corresponds to Proxima b. The second set of possible periods (in red), of around 200 days, are produced from patterns seen in the top panels. The presence of multiple peaks of similar heights means a signal cannot be precisely pinpointed and that its origin remains unclear.</p>
<p>The project will continue acquiring measurements until the end of September this year. You can follow along as the Red Dots campaign unfolds and even contribute observations via the <a href="https://reddots.space">Red Dots website</a>, <a href="https://www.facebook.com/RedDotsSpace/">Facebook</a>, or <a href="https://twitter.com/RedDotsSpace">Twitter</a> accounts.</p>Mon, 11 Sep 2017 11:55:00 +0200http://www.eso.org/public/images/potw1737a/The VLT’s night lighthttp://www.eso.org/public/images/potw1736a/<img src="https://cdn.eso.org/images/news/potw1736a.jpg" border="0" align="left" /><p>This image, taken by <a href="http://www.eso.org/public/outreach/partnerships/photo-ambassadors/">ESO Photo Ambassador</a> Petr Horálek, captures the moment that <a href="https://www.eso.org/public/teles-instr/vlt/vlt-names/yepun/">Yepun (UT4)</a>, one of the four 8.2-metre Unit Telescopes comprising ESO’s <a href="http://eso.org/vlt">Very Large Telescope</a> (VLT), shoots a laser beam up into the dark night sky over ESO’s Paranal Observatory in Chile.</p>
<p dir="ltr">The laser shown in this image acts as an artificial star, known as a <a href="https://en.wikipedia.org/wiki/Laser_guide_star">Laser Guide Star</a>, and it is used to help astronomers adjust for the blurring and distorting effects of the Earth’s atmosphere. When observing a patch of sky, astronomers set up a laser guide star nearby and measure the tiny fluctuations in its image. The VLT’s <a href="https://www.eso.org/public/teles-instr/technology/adaptive_optics/">adaptive optics</a> system can then use this reference to correct for the changes and distortions in the intervening atmosphere and produce the sharpest images possible in the main observations.</p>
<p dir="ltr">Looming over Yepun is the <a href="https://en.wikipedia.org/wiki/Large_Magellanic_Cloud">Large Magellanic Cloud</a> (LMC), a barred <a href="https://en.wikipedia.org/wiki/Spiral_galaxy">spiral galaxy</a> that orbits the <a href="https://en.wikipedia.org/wiki/Milky_Way">Milky Way</a>. A faint white glow marks the location of older stellar populations within the LMC, while the iridescent hues of magenta and blue mark young stellar nurseries.</p>
<p>The LMC, as well as its <a href="https://en.wikipedia.org/wiki/Small_Magellanic_Cloud">smaller namesake</a>, the <a href="https://en.wikipedia.org/wiki/Small_Magellanic_Cloud">Small Magellanic Cloud</a> (SMC), have been studied many times by ESO telescopes over the years. Its many cosmic delights, including nebulae (<a href="http://www.eso.org/public/news/eso0332/">eso0332</a>) and star clusters (<a href="http://www.eso.org/public/news/eso1133/">eso1133</a>), can be seen in detail due to their proximity, and provide amateur and professional astronomers alike with breathtaking targets for observation.</p>Mon, 04 Sep 2017 06:00:00 +0200http://www.eso.org/public/images/potw1736a/